CFSv2 Seasonal SSTs (clim19822010)
first  rec: avg(lastbs-1, lastobs, CFSv2 month 1)
second rec: avg(lastbs, cfs month 1, CFSv2 month 2)
last   rec: CFSv2 month 9
other  rec: CFSv2 3-mo average
 TrgSeason    SST34
   201907     0.25
   201908     0.05
   201909    -0.01
   201910    -0.04
   201911    -0.11
   201912    -0.28
   202001    -0.39
   202002    -0.31
   202003    -0.07
   202004     0.24